enough to reach New York. At the same time, others in Germany had been working feverishly on a radically new payload: a nuclear bomb. Time ran out on the “thousand-year Reich,” and neither project was able to help Hitler.
The ideas, of course, did not go away. One day short of three months after Germany surrendered on May 7, 1945, the United States dropped the first nuclear bomb on Hiroshima. As soon as possible, the United States brought Werner von Braun and many of his fellow rocket scientists to the United States. Russian officials brought other German scientists to the Soviet Union. Soon the U.S. and the U.S.S.R. were building ultra-long-range rockets and testing nuclear bombs. The super-rockets were called Intercontinental Ballistic Missiles (ICBMs) because, like the V 2s, when their engines stopped, they were guided by nothing but the laws of ballistics. They could not be turned back. Similar to the ICBMs are the IRBMs (Intermediate Range Ballistic Missiles).
Since then, guidance systems and other features of these rockets have greatly improved. The latest intercontinental missiles have multiple warheads. The first of these were Multiple Reentry Vehicles (MRVs), which scatter warheads around a single large target to multiply the destruction. A later development was Multiple Independently-targeted Reentry Vehicles (MIRVs). As this rocket descends, warheads and perhaps some decoys are ejected at different points to hit a number of targets. Most diabolical is the MARV system (for Maneuverable Alternative-target Reentry Vehicle. With this system, each warhead has its own rocket, and the warheads can change course to an alternative target if anti-ballistic missile defenses appear.
At present, all of these ICBMs are designed for nuclear warheads. They are far too expensive to waste on mere high-explosive warheads. None of them have ever been used. And the world hopes, they may never be used. All wars and all foreign policy, however, have been conducted with fear of the nuclear-armed ICBM in the background influencing every decision.
Superpowers and even great powers refuse to be stymied because they can’t use the long-range nukes. They do avoid conflict with each other because of the nuclear danger, and they do not even use their nukes on small powers for fear that such action might provoke others to use nuclear weapons. They do, however, use long-range missiles. These missiles, carrying high explosive warheads are much cheaper than ICBMs. They are a development of the old V 1.
Cruise missiles were a major U.S. weapon in both the Gulf War of 1991 and the Iraq War of 2002. There were two types: the Tomahawk and the CALCM (for Conventional Air Launched Cruise Missile). In both wars, the Tomahawk was launched from both surface ships and submarines. Some subs are equipped to launch the missiles through the deck the same way the Polaris ballistic missiles are, others are merely shoot out of the torpedo tubes, after which they rise to the surface and fly away. The CALCMs are launched from B 52 bombers.
They have less range than the Tomahawks, because their launching vehicles can get closer to most targets, but they carry a bigger warhead.
In one way the modern cruise missiles are similar to their V 1 ancestor.
They’re also powered by jet engines (turbofan jets in this case), and they both have a maximum speed of around 590 miles per hour. Their range and accuracy has vastly improved, though. The Tomahawk can travel 1,550 miles and, even at maximum range, it can hit “within meters” of its target. Tomahawks in the Gulf War were guided by a radar system which noted terrain features of the land it was flying over and electronically compared them with topographical information programmed into it. In the Gulf War, this was largely replaced by a global positioning satellite system that was even more accurate.
Tomahawks were the weapon of choice not only in the two Mesopotamian conflicts but in such other situations as during the Clinton administration when U.S. Navy cruise missiles flattened a Sudanese chemical plant that was believed to be producing nerve gas for Al Qaeda and some public buildings in Baghdad in reprisal for an attempt to assassinate former president George H. W. Bush.
Long-range missiles, even without nuclear warheads have changed modern warfare considerably.
Chapter 48
Straight Up: The Helicopter
“The helicopter,” said the famous pioneer, “does with great labor only what a balloon does without labor.” He concluded: “The helicopter is much easier to design than the aeroplane but it is worthless when done.” That was Wilbur Wright in 1906.
Mr. Wright had a point. People had been trying to build helicopters for centuries, and their efforts had produced hardly any results. In 1935, airplanes had reached the altitude of 47,352 feet, attained the speed of 440 miles per hour and had flown non-stop for 5,657 miles. At the same time, the helicopter altitude record was 518 feet, a chopper had reached the speed of 60 miles per hour and another had flown 27 miles.
This was in spite of the fact that Europeans had been making toy helicopters since the 12th century, and the Chinese had been making them even earlier. The toy helicopter was a stick with rotor blades. The stick fitted into a cylinder that was wound up with a string. The operator pulled the string, and the little ’copter flew straight up. Powering the rotor was an early problem. One bright soul in renaissance times suggested that the helicopter pilot pull a rope wound around the rotor the way a child pulled the string of the toy. Aside from the fact that Superman, or his ancestors, was still on the planet Krypton and rope-pulling propulsion awaited his coming, the author of this idea could not explain how the pilot would rewind the rope to continue his flight. Leonardo da Vinci, who did so much futurist thinking, took a shot at helicopter design. His machine had two counter-rotating rotors and was powered by clockwork. Clockwork appeared in many inventions of the 15th and 16th centuries — everything from clocks to wheel lock rifles.
About the only power source available in the 18th and most of the 19th centuries, other than muscle power, was steam. And nobody was able to design a steam engine with a high enough power-to-weight ratio. In 1842, an Englishman named W.H. Phillips flew a jet-powered helicopter, perhaps the first man-carrying jet aircraft in history. Phillips’s machine had jet nozzles on the tips of his rotors. The fuel he burned was an alarming mixture of potassium nitrate, charcoal, and gypsum. Substitute sulfur for gypsum, change the proportions a bit, and you have gunpowder. That early jet carried Phillips several hundred yards, but it was a technological dead end.
Until the internal combustion engine appeared, powered flight in either helicopter or airplane appeared hopeless. But, after the Wright brothers showed the way, the development of airplanes was phenomenally fast, although helicopters were barely able to get off the ground. The trouble was that helicopters had some problems that never occur in airplanes.
One was torque. The huge rotor blades spinning above the helicopter had a tendency to twist the whole ship and drive it off course. If this tendency could not be cured, the helicopter could only fly in a giant circle. The chopper pioneers tried two methods to neutralize torque. One method was to have counter-rotating rotors (like Leonardo’s plan), another was to put a small propeller on the tale. The rotors could also cause another type of twisting — one considerably more dangerous.
Each rotor blade is a kind of wing, generating lift the same way a wing does.
The faster air passes over a wing, the greater the lift it generates. On a helicopter, the blades moving forward generate more lift, because the speed of the air over the blade equals the speed of the blade plus the speed of the craft’s forward motion. The speed of the air over the retreating blade equals the speed of the blade minus the speed of the helicopter’s forward motion. As a result, the helicopter without compensation would roll over. So helicopter progress depended on finding a way to vary the pitch of the rotor blades depending on their direction of motion.
While engineers were working on that problem, a Spaniard named Juan de Cierva invented a new type of rotor plane: the autogyro. The rotors were attached with flapping hinges that let them automatically change their pitch. The rotors were unpowered. The autogyro was propelled by an ordinary aircraft engine and propeller. As the plane gained speed, the rotors turned freely and provided the lift. Some autogyros had a clutch that let the engine supply power to the rotors for a brief time, making possible a straight-up takeoff. Autogyro air mail planes were
